== 參考 https://blog.tiger-workshop.com/ubuntu-postfix-mail-server-msa-dovecot-smtp-authentication/ ==
====== ================= dovecot ================= ======
vi /etc/dovecot/conf.d/10-master.conf
    unix_listener auth-userdb {
      #mode = 0666
      #user = 
      #group = 
    }
  
    # Postfix smtp-auth
    unix_listener /var/spool/postfix/private/auth {
    #  mode = 0666
    }
systemctl start dovecot.service
  10-09 14:35 [root@kiosk postfix]# netstat -anlpt |grep dov
  tcp        0      0 127.0.0.1:995           0.0.0.0:*               LISTEN      2770103/dovecot     
  tcp        0      0 127.0.0.1:110           0.0.0.0:*               LISTEN      2770103/dovecot


  10-09 14:36 [root@kiosk postfix]# lr /var/spool/postfix/private/
  total 0
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 virtual=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 verify=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 trace=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 tlsmgr=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 smtp=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 scache=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 rewrite=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 retry=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 relay=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 proxywrite=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 proxymap=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 policyd-spf=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 local=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 lmtp=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 error=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 discard=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 defer=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 bounce=
  srw-rw-rw- 1 postfix postfix 0 Oct  8 20:37 anvil=
  srw------- 1 root    root    0 Oct  9 14:35 auth=

======  ================= postfix  ================= ======
/etc/postfix/master.cf 修改前：
  10-09 14:53 [root@kiosk postfix]# postconf |grep smtpd_sasl
  smtpd_sasl_auth_enable = no
  smtpd_sasl_authenticated_header = no
  smtpd_sasl_exceptions_networks =
  smtpd_sasl_local_domain =
  smtpd_sasl_mechanism_filter = !external, static:rest
  smtpd_sasl_path = smtpd
  smtpd_sasl_response_limit = 12288
  smtpd_sasl_security_options = noanonymous
  smtpd_sasl_service = smtp
  smtpd_sasl_tls_security_options = $smtpd_sasl_security_options
  smtpd_sasl_type = cyrus
  10-09 15:06 [root@kiosk ssh]# postconf |grep sasl_auth_clients
  broken_sasl_auth_clients = no
  10-09 15:09 [root@kiosk postfix]#
修改 master.cf 的 submission inet 區段：
  submission inet n       -       n       -       -       smtpd
    -o {smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject_unauth_destination,reject_unknown_recipient_domain,reject_unverified_recipient,reject_authenticated_sender_login_mismatch,check_policy_service unix:private/policyd-spf}
    -o smtpd_sasl_auth_enable=yes
    -o smtpd_sasl_local_domain=$myhostname
    -o smtpd_sasl_path=private/auth
    -o smtpd_sasl_type=dovecot
    -o broken_sasl_auth_clients=yes
修改後，systemctl restart postfix.service：
  10-09 15:35 [root@kiosk postfix]# telnet 127.0.0.1 587
  Trying 127.0.0.1...
  Connected to 127.0.0.1.
  Escape character is '^]'.
  220 mail.feuer.idv.tw ESMTP Gabriel (3.8.1) (Mageia Linux)
  quit
  221 2.0.0 Bye
  Connection closed by foreign host.